Former US congresswoman Gabby Giffords, who was seriously wounded in a 2011 mass shooting, has made an emotional plea for Congress to take action to curb gun violence.
Giffords opened testimony on Wednesday at the first congressional hearing on gun violence urging lawmakers to "be bold, be courageous".
The hearing was prompted by the December 14 incident in which a gunman shot dead 20 children and six adults at an elementary school in Newtown, Connecticut.
Responding to outrage across the country following that massacre, President Barack Obama and other Democrats have asked Congress to pass the largest package of gun restrictions in decades.
"This is an important conversation for our children, for our communities, for Democrats and Republicans," Giffords, who survived a head wound in a mass shooting in Tucson, Arizona, told the Senate Judiciary Committee.
Six people were killed and 13 wounded in the incident.
"Speaking is difficult. But I need to say something important," she told the senators. "Violence is a big problem. Too many children are dying - too many children. We must do something. It will be hard. But the time is now."
Accompanied by her husband, former astronaut Mark Kelly, she concluded: "You must act. Be bold, be courageous. Americans are counting on you. Thank you." She did not take questions from the committee.
Obama's proposals to curb gun violence include reinstating the US ban on military-style assault weapons, limiting the capacity of ammunition magazines, and more extensive background checks of prospective gun buyers, largely to verify whether they have a history of crime or mental illness.
Wayne LaPierre, executive vice president and CEO of the powerful pro-gun lobbying group the National Rifle Association, said the proposals would not reduce gun violence and called for more active prosecution of current laws and improved protection for schools, including armed guards.
LaPierre has also said that posting armed guards in schools would prevent massacres such as the one in Newtown, insisting that, "The only thing that stops a bad guy with a gun is a good guy with a gun."
Obama's proposals face a difficult challenge getting through the Democratic-led Senate and Republican-led House of Representatives, where many Republicans and some pro-gun Democrats have long opposed stronger restrictions.
The background check provision is regarded as the gun-control measure most likely to receive bipartisan support.
Some Republicans have joined Democrats in emphasizing better background checks of gun buyers, rather than Obama's plan to ban the sale of rapid-firing assault weapons like the one used in the Connecticut shootings.
Federally licensed firearms dealers are required to run background checks for criminal records on gun buyers.
But the government estimates that 40 percent of purchasers avoid screening by getting their guns from private sellers, including those at gun shows.
The White House's plan would require screening for all prospective buyers.
Kelly, who also testified, and Giffords recently founded Americans for Responsible Solutions, a group intended to combat gun violence.
"Gabby and I are pro-gun ownership. We are also anti-gun violence," Kelly told the senators.